The in-vitro evaluation of antibacterial, antifungal and cytotoxic properties of Marrubium vulgare L. essential oil grown in Tunisia

<p>Abstract</p> <p>Background</p> <p>In order to validate its antiseptic and anticancer properties with respect to traditional uses, we have screened for the first time the antimicrobial activity of aerial parts of <it>M. vulgare </it>L. essential oil against different pathogenic microorganisms and the cytotoxic activity against HeLa cell lines.</p> <p>Methods</p> <p>The agar disk diffusion method was used to study the antibacterial activity of <it>M. vulgare </it>essential oil against 12 bacterial and 4 fungi strains. The disc diameters of zone of inhibition (DD), the minimum inhibitory concentrations (MIC) and the concentration inhibiting 50% (IC₅₀) were investigated to characterize the antimicrobial activities of this essential oil. The <it>in vitro </it>cytotoxicity of <it>M. vulgare </it>essential oil was examined using a modified MTT assay; the viability and the IC₅₀were used to evaluate this test.</p> <p>Results</p> <p>The antimicrobial activity of the essential oil was investigated in order to evaluate its efficacy against the different tested microorganisms. The present results results showed a significant activity against microorganisms especially Gram (+) bacteria with inhibition zones and minimal inhibitory concentration values in the range of 6.6-25.2 mm and 1120-2600 μg/ml, respectively, whereas Gram (-) bacteria exhibited a higher resistance. As far as the antifungal activity, among four strains tested, <it>Botrytis cinerea </it>exhibited the strongest activity with inhibition zones of 12.6 mm. However, <it>Fusarium solani, Penicillium digitatum </it>and <it>Aspergillus niger </it>were less sensitive to <it>M. vulgare </it>essential oil. About the citotoxicity assay, this finding indicate the capability of this essential oil to inhibited the proliferation of HeLa cell lines under some conditions with IC₅₀value of 0.258 μg/ml.</p> <p>Conclusion</p> <p>This investigation showed that the <it>M. vulgare </it>essential oil has a potent antimicrobial activity against some Gram (+) pathogenic bacteria and <it>Botrytis cinerea </it>fungi. The present studies confirm the use of this essential oil as anticancer agent. Further research is required to evaluate the practical values of therapeutic applications.</p

Detection of JavaScript Injection Eavesdropping on WebRTC communications

WebRTC is a Google-developed project that allows users to communicate directly. It is an open-source tool supported by all major browsers. Since it does not require additional installation steps and provides ultra-low latency streaming, smart city and social network applications such as WhatsApp, Facebook Messenger, and Snapchat use it as the underlying technology on the client-side both on desktop browsers and mobile apps. While the open-source tool is deemed to be secure and despite years of research and security testing, there are still vulnerabilities in the real-time communication application programming interface (API). We show in this paper how eavesdropping can be enabled by exploiting weaknesses and loopholes found in official WebRTC specifications. We demonstrate through real-world implementation how an eavesdropper can intercept WebRTC video calls by installing a malicious code onto the WebRTC webserver. Furthermore, we identify and discuss several, easy to perform, ways to detect wiretapping. Our evaluation shows that several indicators within webrtc-internals API traces can be used to detect anomalous activities, without the need for network monitoring tools

Differential Flatness-Based Performance Enhancement of a Vector Controlled VSC with an LCL-Filter for Weak Grids

In this paper, a novel single-loop flatness-based controller (FBC) is proposed to control the grid-side current in a shunt converter connected to a weak grid through an LCL-filter. After its mathematical description, the paper reports controller implementation and some performance comparisons with two distinct implementations of the widely diffused vector current control approach, during balanced and unbalanced grid voltages, and weak grid conditions. Obtained results highlight higher tracking capability and better dynamic response of the proposed FBC. Moreover, because of its reduced negative conductance region, unstable behaviors that can be observed in weak grids appear significantly improved due to a reduced influence of the phase-locked loop system

Involvement of Different CD4 + T Cell Subsets Producing Granzyme B in the Immune Response to Leishmania major Antigens

The nature of effector cells and the potential immunogenicity of Leishmania major excreted/secreted proteins (LmES) were evaluated using peripheral blood mononuclear cells (PBMCs) from healed zoonotic cutaneous leishmaniasis individuals (HZCL) and healthy controls (HC). First, we found that PBMCs from HZCL individuals proliferate and produce high levels of IFN-and granzyme B (GrB), used as a marker of activated cytotoxic T cells, in response to the parasite antigens. IFN-is produced by CD4 + T cells, but unexpectedly GrB is also produced by CD4 + T cells in response to stimulation with LmES, which were found to be as effective as soluble Leishmania antigens to induce proliferation and cytokine production by PBMCs from immune individuals. To address the question of regulatory T cell (Tregs) involvement, the frequency of circulating Tregs was assessed and found to be higher in HZCL individuals compared to that of HC. Furthermore, both CD4 + CD25 + and CD4 + CD25 − T cells, purified from HZCL individuals, produced IFN-and GrB when stimulated with LmES. Additional experiments showed that CD4 + CD25 + CD127 dim/− Tregs were involved in GrB production. Collectively, our data indicate that LmES are immunogenic in humans and emphasize the involvement of CD4 + T cells including activated and regulatory T cells in the immune response against parasite antigens

Super-spreading social events for COVID-19 transmission: evidence from the investigation of six early clusters in Bahrain

IntroductionThis study aimed to characterize six early clusters of COVID-19 and derive key transmission parameters from confirmed cases that were traced between April and June 2020 in Bahrain.MethodsPairs of “infector-infectee” allowed us to map the clusters and estimate the incubation period serial interval as the secondary attack rate. The chi-squared test, with a p-value computed using the Monte Carlo test, measured associations between categorical variables. Statistical analysis was performed using R software and the “data.tree, tidyverse” libraries.ResultsFrom 9 April to 27 June 2020, we investigated 596 individuals suspected of COVID-19, of whom 127 positive cases were confirmed by PCR and linked in six clusters. The mean age was 30.34 years (S.D. = 17.84 years). The male-to-female ratio was 0.87 (276/318), and most of the contacts were of Bahraini citizenship (511/591 = 86.5%). Exposure occurred within the family in 74.3% (411/553), and 18.9% of clusters' cases were symptomatic (23/122 = 18.9%). Mapped clusters and generations increased after 24 May 2020, corresponding to “Aid El-Fitr.” The mean incubation period was 4 days, and the mean serial interval ranged from 3 to 3.31 days. The secondary attack rate was 0.21 (95% C.I.) = [0.17–0.24].ConclusionCOVID-19 transmission was amplified due to the high number of families mixing during “Aid El Fitr” and “Ramadhan,” generating important clusters. Estimated serial intervals and incubation periods support asymptomatic transmission

Plant mediated synthesis of flower-like Cu2O microbeads from Artimisia campestris L. extract for the catalyzed synthesis of 1,4-disubstituted 1,2,3-triazole derivatives

This study presents a novel method for synthesizing 1,4-disubstituted 1,2,3-triazole derivatives through a one-pot, multi-component addition reaction using flower-like Cu2O microbeads as a catalyst. The flower-like Cu2O microbeads were synthesized using an aqueous extract of Artimisia Campestris L. This extract demonstrated the capability to reduce and stabilize Cu2O particles during their initial formation, resulting in the formation of a porous flower-like morphology. These Cu2O microbeads exhibit distinctive features, including a cubic close-packed (ccp) crystal structure with an average crystallite size of 22.8 nm, bandgap energy of 2.7 eV and a particle size of 6 µm. Their catalytic activity in synthesizing 1,4-disubstituted 1,2,3-triazole derivatives was investigated through systematic exploration of key parameters such as catalyst quantity (1, 5, 10, 15, 20, and 30 mg/mL), solvent type (dimethylformamide/H2O, ethanol/H2O, dichloromethane/H2O, chloroform, acetone, and dimethyl sulfoxide), and catalyst reusability (four cycles). The Cu2O microbeads significantly increased the product yield from 20% to 85.3%. The green synthesis and outstanding catalytic attributes make these flower-like Cu2O microbeads promising, efficient, and recyclable catalysts for sustainable and effective chemical transformations

Anaesthetic Considerations in Gastrointestinal Endoscopies

Gastrointestinal endoscopy has become fundamental procedure for diagnosis and treatment of gastrointestinal tract diseases. Generally, the gastrointestinal endoscopy is minimally invasive procedure. However, it can cause considerable amount of discomfort and pain which make the procedure unsafe, complicated and refusal of follow up procedures if done without safe sedation. The sedation is required to alleviate anxiety, provide analgesia, amnesia and to improve endoscopic performance specifically in therapeutic procedures. The safe administration of sedative and analgesic medications, irrespective of the regimen used, requires knowledge of the individual needs of patients. The combination of benzodiazepines and opioids is now the most widely used sedation regimen for sedation in gastrointestinal endoscopic procedures. Generally, sedation for gastrointestinal endoscopy is considered safe, however, it has the potential for serious complications. Therefore, endoscopist should assess the patients properly before the endoscopy as well as should be aware of all possible complications and the risk factors. Furthermore, skilled staff and emergency equipment should be available in endoscopy suit. This chapter discuss in details all the aspects of safe procedural sedation during GI endoscopies